The number of youth with type 2 diabetes in the U.S. is projected to increase by a staggering 49 percent by 2050, with higher rates among minority youth. The Diabetes Prevention Program (DPP) is recognized as a sentinel study demonstrating the effectiveness of lifestyle interventions for diabetes prevention among pre- diabetic adults but has not yet been replicated in youth. In addition, such intensive interventions are often not sustainable in high risk communities with limited resources. One strategy that has been successfully employed in adults from such communities is peer based health education. Research suggests that like adults, young people are more likely to hear and personalize messages, and thus to change their attitudes and behaviors, if they believe the messenger is similar to them and faces the same concerns and pressures. However, there have been no peer led interventions in ethnic minority teens and no interventions focused specifically on weight loss for diabetes prevention. Finally, another challenge identified in existing youth health intervention programs is keeping youth engaged to enhance program participation and impact. One potential strategy is the use of mobile technologies (text messaging, mobile applications, social media) to support weight management programs, but to date use of such technologies has not been studied in youth. This proposal's overall objective is to use community-based participatory research (CBPR) to develop and pilot test a youth peer-led diabetes prevention intervention incorporating novel mobile health technologies for at-risk adolescents in a vulnerable New York City community. The central hypothesis is that such an intervention will lead to maintenance or decrease in BMI, improved dietary, physical activity and weight control behaviors, and decrease in diabetes risk, Specific Aims: 1) Explore strategies for using peer educators and novel mobile health technologies as part of a group lifestyle change program for diabetes prevention among at-risk ethnic minority youth in a New York City community with high disease burden. 2) Design, pilot test, and evaluate preliminary outcomes for the intervention. Using data from Aim 1, we will use CBPR to translate a proven adult peer led diabetes prevention intervention into a developmentally and culturally appropriate lifestyle intervention for pre-diabetic ethnic minority adolescents. We will then screen at-risk adolescents for pre-diabetes and related lifestyle and biological measures and compare outcomes in pre-diabetic adolescents in intervention and wait list control groups to test intervention effectivenes. 3) Further refine the pilot intervention for a larger RCT based on an examination of intervention feasibility, acceptability, and sustainability,